This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A133633 #12 Dec 31 2011 13:45:33 %S A133633 25,35,49,55,65,77,85,91,95,115,119,121,125,133,143,145,155 %N A133633 Duplicate of A038509. %K A133633 dead %O A133633 1,1